Comments: This species was transferred to Ciconiiformes (AOU 1998) but subsequently was tentatively returned to the order Falconiformes after re-evaluation of the reasons for the earlier change. Further, some genetic studies (Cracraft et al. 2004, Fain and Houde 2004, Ericson et al. 2006) indicate that New World vultures are not closely related to storks, although their precise phylogenetic relationship to the Falconiformes is yet undetermined (AOU 2007).